In this correction to his work "A New Determination of Molecular Dimensions," Albert Einstein addresses an error in his calculations regarding the viscosity of suspensions. The error, discovered by Hr. Hopf, affects the expressions for the stress components \(X_y\) and \(X_z\) on page 296 of the paper. The corrected expressions are provided, and it is noted that the total volume \(\varphi\) of the suspended spheres significantly influences the viscosity coefficient \(k^*\) of the suspension. Specifically, \(k^*\) is found to be 2.5 times more affected by \(\varphi\) than previously thought. Using the corrected formula, Einstein provides new values for the volume of 1 gram of dissolved sugar in water and the number of molecules per gram molecule in diluted sugar solutions, which differ from those previously reported.In this correction to his work "A New Determination of Molecular Dimensions," Albert Einstein addresses an error in his calculations regarding the viscosity of suspensions. The error, discovered by Hr. Hopf, affects the expressions for the stress components \(X_y\) and \(X_z\) on page 296 of the paper. The corrected expressions are provided, and it is noted that the total volume \(\varphi\) of the suspended spheres significantly influences the viscosity coefficient \(k^*\) of the suspension. Specifically, \(k^*\) is found to be 2.5 times more affected by \(\varphi\) than previously thought. Using the corrected formula, Einstein provides new values for the volume of 1 gram of dissolved sugar in water and the number of molecules per gram molecule in diluted sugar solutions, which differ from those previously reported.